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- #include <linux/kernel.h>
- #include <linux/skbuff.h>
- #include <linux/export.h>
- #include <linux/ip.h>
- #include <linux/ipv6.h>
- #include <linux/if_vlan.h>
- #include <net/dsa.h>
- #include <net/dst_metadata.h>
- #include <net/ip.h>
- #include <net/ipv6.h>
- #include <net/gre.h>
- #include <net/pptp.h>
- #include <net/tipc.h>
- #include <linux/igmp.h>
- #include <linux/icmp.h>
- #include <linux/sctp.h>
- #include <linux/dccp.h>
- #include <linux/if_tunnel.h>
- #include <linux/if_pppox.h>
- #include <linux/ppp_defs.h>
- #include <linux/stddef.h>
- #include <linux/if_ether.h>
- #include <linux/mpls.h>
- #include <linux/tcp.h>
- #include <net/flow_dissector.h>
- #include <scsi/fc/fc_fcoe.h>
- #include <uapi/linux/batadv_packet.h>
- static void dissector_set_key(struct flow_dissector *flow_dissector,
- enum flow_dissector_key_id key_id)
- {
- flow_dissector->used_keys |= (1 << key_id);
- }
- void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
- const struct flow_dissector_key *key,
- unsigned int key_count)
- {
- unsigned int i;
- memset(flow_dissector, 0, sizeof(*flow_dissector));
- for (i = 0; i < key_count; i++, key++) {
- /* User should make sure that every key target offset is withing
- * boundaries of unsigned short.
- */
- BUG_ON(key->offset > USHRT_MAX);
- BUG_ON(dissector_uses_key(flow_dissector,
- key->key_id));
- dissector_set_key(flow_dissector, key->key_id);
- flow_dissector->offset[key->key_id] = key->offset;
- }
- /* Ensure that the dissector always includes control and basic key.
- * That way we are able to avoid handling lack of these in fast path.
- */
- BUG_ON(!dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_CONTROL));
- BUG_ON(!dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_BASIC));
- }
- EXPORT_SYMBOL(skb_flow_dissector_init);
- /**
- * skb_flow_get_be16 - extract be16 entity
- * @skb: sk_buff to extract from
- * @poff: offset to extract at
- * @data: raw buffer pointer to the packet
- * @hlen: packet header length
- *
- * The function will try to retrieve a be32 entity at
- * offset poff
- */
- static __be16 skb_flow_get_be16(const struct sk_buff *skb, int poff,
- void *data, int hlen)
- {
- __be16 *u, _u;
- u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
- if (u)
- return *u;
- return 0;
- }
- /**
- * __skb_flow_get_ports - extract the upper layer ports and return them
- * @skb: sk_buff to extract the ports from
- * @thoff: transport header offset
- * @ip_proto: protocol for which to get port offset
- * @data: raw buffer pointer to the packet, if NULL use skb->data
- * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
- *
- * The function will try to retrieve the ports at offset thoff + poff where poff
- * is the protocol port offset returned from proto_ports_offset
- */
- __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
- void *data, int hlen)
- {
- int poff = proto_ports_offset(ip_proto);
- if (!data) {
- data = skb->data;
- hlen = skb_headlen(skb);
- }
- if (poff >= 0) {
- __be32 *ports, _ports;
- ports = __skb_header_pointer(skb, thoff + poff,
- sizeof(_ports), data, hlen, &_ports);
- if (ports)
- return *ports;
- }
- return 0;
- }
- EXPORT_SYMBOL(__skb_flow_get_ports);
- static void
- skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
- struct flow_dissector *flow_dissector,
- void *target_container)
- {
- struct flow_dissector_key_control *ctrl;
- if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
- return;
- ctrl = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_CONTROL,
- target_container);
- ctrl->addr_type = type;
- }
- void
- skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container)
- {
- struct ip_tunnel_info *info;
- struct ip_tunnel_key *key;
- /* A quick check to see if there might be something to do. */
- if (!dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_KEYID) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_PORTS) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IP) &&
- !dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_OPTS))
- return;
- info = skb_tunnel_info(skb);
- if (!info)
- return;
- key = &info->key;
- switch (ip_tunnel_info_af(info)) {
- case AF_INET:
- skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
- flow_dissector,
- target_container);
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
- struct flow_dissector_key_ipv4_addrs *ipv4;
- ipv4 = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
- target_container);
- ipv4->src = key->u.ipv4.src;
- ipv4->dst = key->u.ipv4.dst;
- }
- break;
- case AF_INET6:
- skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
- flow_dissector,
- target_container);
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
- struct flow_dissector_key_ipv6_addrs *ipv6;
- ipv6 = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
- target_container);
- ipv6->src = key->u.ipv6.src;
- ipv6->dst = key->u.ipv6.dst;
- }
- break;
- }
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
- struct flow_dissector_key_keyid *keyid;
- keyid = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_KEYID,
- target_container);
- keyid->keyid = tunnel_id_to_key32(key->tun_id);
- }
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
- struct flow_dissector_key_ports *tp;
- tp = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_PORTS,
- target_container);
- tp->src = key->tp_src;
- tp->dst = key->tp_dst;
- }
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
- struct flow_dissector_key_ip *ip;
- ip = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_IP,
- target_container);
- ip->tos = key->tos;
- ip->ttl = key->ttl;
- }
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
- struct flow_dissector_key_enc_opts *enc_opt;
- enc_opt = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ENC_OPTS,
- target_container);
- if (info->options_len) {
- enc_opt->len = info->options_len;
- ip_tunnel_info_opts_get(enc_opt->data, info);
- enc_opt->dst_opt_type = info->key.tun_flags &
- TUNNEL_OPTIONS_PRESENT;
- }
- }
- }
- EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
- static enum flow_dissect_ret
- __skb_flow_dissect_mpls(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data, int nhoff, int hlen)
- {
- struct flow_dissector_key_keyid *key_keyid;
- struct mpls_label *hdr, _hdr[2];
- u32 entry, label;
- if (!dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
- !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
- return FLOW_DISSECT_RET_OUT_GOOD;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
- hlen, &_hdr);
- if (!hdr)
- return FLOW_DISSECT_RET_OUT_BAD;
- entry = ntohl(hdr[0].entry);
- label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
- struct flow_dissector_key_mpls *key_mpls;
- key_mpls = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_MPLS,
- target_container);
- key_mpls->mpls_label = label;
- key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
- >> MPLS_LS_TTL_SHIFT;
- key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
- >> MPLS_LS_TC_SHIFT;
- key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
- >> MPLS_LS_S_SHIFT;
- }
- if (label == MPLS_LABEL_ENTROPY) {
- key_keyid = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
- target_container);
- key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
- }
- return FLOW_DISSECT_RET_OUT_GOOD;
- }
- static enum flow_dissect_ret
- __skb_flow_dissect_arp(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data, int nhoff, int hlen)
- {
- struct flow_dissector_key_arp *key_arp;
- struct {
- unsigned char ar_sha[ETH_ALEN];
- unsigned char ar_sip[4];
- unsigned char ar_tha[ETH_ALEN];
- unsigned char ar_tip[4];
- } *arp_eth, _arp_eth;
- const struct arphdr *arp;
- struct arphdr _arp;
- if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
- return FLOW_DISSECT_RET_OUT_GOOD;
- arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
- hlen, &_arp);
- if (!arp)
- return FLOW_DISSECT_RET_OUT_BAD;
- if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
- arp->ar_pro != htons(ETH_P_IP) ||
- arp->ar_hln != ETH_ALEN ||
- arp->ar_pln != 4 ||
- (arp->ar_op != htons(ARPOP_REPLY) &&
- arp->ar_op != htons(ARPOP_REQUEST)))
- return FLOW_DISSECT_RET_OUT_BAD;
- arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
- sizeof(_arp_eth), data,
- hlen, &_arp_eth);
- if (!arp_eth)
- return FLOW_DISSECT_RET_OUT_BAD;
- key_arp = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ARP,
- target_container);
- memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
- memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
- /* Only store the lower byte of the opcode;
- * this covers ARPOP_REPLY and ARPOP_REQUEST.
- */
- key_arp->op = ntohs(arp->ar_op) & 0xff;
- ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
- ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
- return FLOW_DISSECT_RET_OUT_GOOD;
- }
- static enum flow_dissect_ret
- __skb_flow_dissect_gre(const struct sk_buff *skb,
- struct flow_dissector_key_control *key_control,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data,
- __be16 *p_proto, int *p_nhoff, int *p_hlen,
- unsigned int flags)
- {
- struct flow_dissector_key_keyid *key_keyid;
- struct gre_base_hdr *hdr, _hdr;
- int offset = 0;
- u16 gre_ver;
- hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
- data, *p_hlen, &_hdr);
- if (!hdr)
- return FLOW_DISSECT_RET_OUT_BAD;
- /* Only look inside GRE without routing */
- if (hdr->flags & GRE_ROUTING)
- return FLOW_DISSECT_RET_OUT_GOOD;
- /* Only look inside GRE for version 0 and 1 */
- gre_ver = ntohs(hdr->flags & GRE_VERSION);
- if (gre_ver > 1)
- return FLOW_DISSECT_RET_OUT_GOOD;
- *p_proto = hdr->protocol;
- if (gre_ver) {
- /* Version1 must be PPTP, and check the flags */
- if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
- return FLOW_DISSECT_RET_OUT_GOOD;
- }
- offset += sizeof(struct gre_base_hdr);
- if (hdr->flags & GRE_CSUM)
- offset += sizeof(((struct gre_full_hdr *) 0)->csum) +
- sizeof(((struct gre_full_hdr *) 0)->reserved1);
- if (hdr->flags & GRE_KEY) {
- const __be32 *keyid;
- __be32 _keyid;
- keyid = __skb_header_pointer(skb, *p_nhoff + offset,
- sizeof(_keyid),
- data, *p_hlen, &_keyid);
- if (!keyid)
- return FLOW_DISSECT_RET_OUT_BAD;
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_GRE_KEYID)) {
- key_keyid = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_GRE_KEYID,
- target_container);
- if (gre_ver == 0)
- key_keyid->keyid = *keyid;
- else
- key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
- }
- offset += sizeof(((struct gre_full_hdr *) 0)->key);
- }
- if (hdr->flags & GRE_SEQ)
- offset += sizeof(((struct pptp_gre_header *) 0)->seq);
- if (gre_ver == 0) {
- if (*p_proto == htons(ETH_P_TEB)) {
- const struct ethhdr *eth;
- struct ethhdr _eth;
- eth = __skb_header_pointer(skb, *p_nhoff + offset,
- sizeof(_eth),
- data, *p_hlen, &_eth);
- if (!eth)
- return FLOW_DISSECT_RET_OUT_BAD;
- *p_proto = eth->h_proto;
- offset += sizeof(*eth);
- /* Cap headers that we access via pointers at the
- * end of the Ethernet header as our maximum alignment
- * at that point is only 2 bytes.
- */
- if (NET_IP_ALIGN)
- *p_hlen = *p_nhoff + offset;
- }
- } else { /* version 1, must be PPTP */
- u8 _ppp_hdr[PPP_HDRLEN];
- u8 *ppp_hdr;
- if (hdr->flags & GRE_ACK)
- offset += sizeof(((struct pptp_gre_header *) 0)->ack);
- ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
- sizeof(_ppp_hdr),
- data, *p_hlen, _ppp_hdr);
- if (!ppp_hdr)
- return FLOW_DISSECT_RET_OUT_BAD;
- switch (PPP_PROTOCOL(ppp_hdr)) {
- case PPP_IP:
- *p_proto = htons(ETH_P_IP);
- break;
- case PPP_IPV6:
- *p_proto = htons(ETH_P_IPV6);
- break;
- default:
- /* Could probably catch some more like MPLS */
- break;
- }
- offset += PPP_HDRLEN;
- }
- *p_nhoff += offset;
- key_control->flags |= FLOW_DIS_ENCAPSULATION;
- if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
- return FLOW_DISSECT_RET_OUT_GOOD;
- return FLOW_DISSECT_RET_PROTO_AGAIN;
- }
- /**
- * __skb_flow_dissect_batadv() - dissect batman-adv header
- * @skb: sk_buff to with the batman-adv header
- * @key_control: flow dissectors control key
- * @data: raw buffer pointer to the packet, if NULL use skb->data
- * @p_proto: pointer used to update the protocol to process next
- * @p_nhoff: pointer used to update inner network header offset
- * @hlen: packet header length
- * @flags: any combination of FLOW_DISSECTOR_F_*
- *
- * ETH_P_BATMAN packets are tried to be dissected. Only
- * &struct batadv_unicast packets are actually processed because they contain an
- * inner ethernet header and are usually followed by actual network header. This
- * allows the flow dissector to continue processing the packet.
- *
- * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
- * FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
- * otherwise FLOW_DISSECT_RET_OUT_BAD
- */
- static enum flow_dissect_ret
- __skb_flow_dissect_batadv(const struct sk_buff *skb,
- struct flow_dissector_key_control *key_control,
- void *data, __be16 *p_proto, int *p_nhoff, int hlen,
- unsigned int flags)
- {
- struct {
- struct batadv_unicast_packet batadv_unicast;
- struct ethhdr eth;
- } *hdr, _hdr;
- hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
- &_hdr);
- if (!hdr)
- return FLOW_DISSECT_RET_OUT_BAD;
- if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
- return FLOW_DISSECT_RET_OUT_BAD;
- if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
- return FLOW_DISSECT_RET_OUT_BAD;
- *p_proto = hdr->eth.h_proto;
- *p_nhoff += sizeof(*hdr);
- key_control->flags |= FLOW_DIS_ENCAPSULATION;
- if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
- return FLOW_DISSECT_RET_OUT_GOOD;
- return FLOW_DISSECT_RET_PROTO_AGAIN;
- }
- static void
- __skb_flow_dissect_tcp(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data, int thoff, int hlen)
- {
- struct flow_dissector_key_tcp *key_tcp;
- struct tcphdr *th, _th;
- if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
- return;
- th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
- if (!th)
- return;
- if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
- return;
- key_tcp = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_TCP,
- target_container);
- key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
- }
- static void
- __skb_flow_dissect_ipv4(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data, const struct iphdr *iph)
- {
- struct flow_dissector_key_ip *key_ip;
- if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
- return;
- key_ip = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_IP,
- target_container);
- key_ip->tos = iph->tos;
- key_ip->ttl = iph->ttl;
- }
- static void
- __skb_flow_dissect_ipv6(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container, void *data, const struct ipv6hdr *iph)
- {
- struct flow_dissector_key_ip *key_ip;
- if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
- return;
- key_ip = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_IP,
- target_container);
- key_ip->tos = ipv6_get_dsfield(iph);
- key_ip->ttl = iph->hop_limit;
- }
- /* Maximum number of protocol headers that can be parsed in
- * __skb_flow_dissect
- */
- #define MAX_FLOW_DISSECT_HDRS 15
- static bool skb_flow_dissect_allowed(int *num_hdrs)
- {
- ++*num_hdrs;
- return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
- }
- /**
- * __skb_flow_dissect - extract the flow_keys struct and return it
- * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
- * @flow_dissector: list of keys to dissect
- * @target_container: target structure to put dissected values into
- * @data: raw buffer pointer to the packet, if NULL use skb->data
- * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
- * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
- * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
- *
- * The function will try to retrieve individual keys into target specified
- * by flow_dissector from either the skbuff or a raw buffer specified by the
- * rest parameters.
- *
- * Caller must take care of zeroing target container memory.
- */
- bool __skb_flow_dissect(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container,
- void *data, __be16 proto, int nhoff, int hlen,
- unsigned int flags)
- {
- struct flow_dissector_key_control *key_control;
- struct flow_dissector_key_basic *key_basic;
- struct flow_dissector_key_addrs *key_addrs;
- struct flow_dissector_key_ports *key_ports;
- struct flow_dissector_key_icmp *key_icmp;
- struct flow_dissector_key_tags *key_tags;
- struct flow_dissector_key_vlan *key_vlan;
- enum flow_dissect_ret fdret;
- enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
- int num_hdrs = 0;
- u8 ip_proto = 0;
- bool ret;
- if (!data) {
- data = skb->data;
- proto = skb_vlan_tag_present(skb) ?
- skb->vlan_proto : skb->protocol;
- nhoff = skb_network_offset(skb);
- hlen = skb_headlen(skb);
- #if IS_ENABLED(CONFIG_NET_DSA)
- if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
- proto == htons(ETH_P_XDSA))) {
- const struct dsa_device_ops *ops;
- int offset = 0;
- ops = skb->dev->dsa_ptr->tag_ops;
- if (ops->flow_dissect &&
- !ops->flow_dissect(skb, &proto, &offset)) {
- hlen -= offset;
- nhoff += offset;
- }
- }
- #endif
- }
- /* It is ensured by skb_flow_dissector_init() that control key will
- * be always present.
- */
- key_control = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_CONTROL,
- target_container);
- /* It is ensured by skb_flow_dissector_init() that basic key will
- * be always present.
- */
- key_basic = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_BASIC,
- target_container);
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
- struct ethhdr *eth = eth_hdr(skb);
- struct flow_dissector_key_eth_addrs *key_eth_addrs;
- key_eth_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ETH_ADDRS,
- target_container);
- memcpy(key_eth_addrs, ð->h_dest, sizeof(*key_eth_addrs));
- }
- proto_again:
- fdret = FLOW_DISSECT_RET_CONTINUE;
- switch (proto) {
- case htons(ETH_P_IP): {
- const struct iphdr *iph;
- struct iphdr _iph;
- iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
- if (!iph || iph->ihl < 5) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- nhoff += iph->ihl * 4;
- ip_proto = iph->protocol;
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
- key_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV4_ADDRS,
- target_container);
- memcpy(&key_addrs->v4addrs, &iph->saddr,
- sizeof(key_addrs->v4addrs));
- key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
- }
- if (ip_is_fragment(iph)) {
- key_control->flags |= FLOW_DIS_IS_FRAGMENT;
- if (iph->frag_off & htons(IP_OFFSET)) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- } else {
- key_control->flags |= FLOW_DIS_FIRST_FRAG;
- if (!(flags &
- FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- }
- }
- __skb_flow_dissect_ipv4(skb, flow_dissector,
- target_container, data, iph);
- if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- break;
- }
- case htons(ETH_P_IPV6): {
- const struct ipv6hdr *iph;
- struct ipv6hdr _iph;
- iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
- if (!iph) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- ip_proto = iph->nexthdr;
- nhoff += sizeof(struct ipv6hdr);
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
- key_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV6_ADDRS,
- target_container);
- memcpy(&key_addrs->v6addrs, &iph->saddr,
- sizeof(key_addrs->v6addrs));
- key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
- }
- if ((dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
- (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
- ip6_flowlabel(iph)) {
- __be32 flow_label = ip6_flowlabel(iph);
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
- key_tags = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_FLOW_LABEL,
- target_container);
- key_tags->flow_label = ntohl(flow_label);
- }
- if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- }
- __skb_flow_dissect_ipv6(skb, flow_dissector,
- target_container, data, iph);
- if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- case htons(ETH_P_8021AD):
- case htons(ETH_P_8021Q): {
- const struct vlan_hdr *vlan = NULL;
- struct vlan_hdr _vlan;
- __be16 saved_vlan_tpid = proto;
- if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
- skb && skb_vlan_tag_present(skb)) {
- proto = skb->protocol;
- } else {
- vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
- data, hlen, &_vlan);
- if (!vlan) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- proto = vlan->h_vlan_encapsulated_proto;
- nhoff += sizeof(*vlan);
- }
- if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
- dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
- } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
- dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
- } else {
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- }
- if (dissector_uses_key(flow_dissector, dissector_vlan)) {
- key_vlan = skb_flow_dissector_target(flow_dissector,
- dissector_vlan,
- target_container);
- if (!vlan) {
- key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
- key_vlan->vlan_priority =
- (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
- } else {
- key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
- VLAN_VID_MASK;
- key_vlan->vlan_priority =
- (ntohs(vlan->h_vlan_TCI) &
- VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
- }
- key_vlan->vlan_tpid = saved_vlan_tpid;
- }
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- }
- case htons(ETH_P_PPP_SES): {
- struct {
- struct pppoe_hdr hdr;
- __be16 proto;
- } *hdr, _hdr;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
- if (!hdr) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- proto = hdr->proto;
- nhoff += PPPOE_SES_HLEN;
- switch (proto) {
- case htons(PPP_IP):
- proto = htons(ETH_P_IP);
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- case htons(PPP_IPV6):
- proto = htons(ETH_P_IPV6);
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- default:
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- break;
- }
- case htons(ETH_P_TIPC): {
- struct tipc_basic_hdr *hdr, _hdr;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
- data, hlen, &_hdr);
- if (!hdr) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_TIPC)) {
- key_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_TIPC,
- target_container);
- key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
- key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
- }
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- case htons(ETH_P_MPLS_UC):
- case htons(ETH_P_MPLS_MC):
- fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
- target_container, data,
- nhoff, hlen);
- break;
- case htons(ETH_P_FCOE):
- if ((hlen - nhoff) < FCOE_HEADER_LEN) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- nhoff += FCOE_HEADER_LEN;
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- case htons(ETH_P_ARP):
- case htons(ETH_P_RARP):
- fdret = __skb_flow_dissect_arp(skb, flow_dissector,
- target_container, data,
- nhoff, hlen);
- break;
- case htons(ETH_P_BATMAN):
- fdret = __skb_flow_dissect_batadv(skb, key_control, data,
- &proto, &nhoff, hlen, flags);
- break;
- default:
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- /* Process result of proto processing */
- switch (fdret) {
- case FLOW_DISSECT_RET_OUT_GOOD:
- goto out_good;
- case FLOW_DISSECT_RET_PROTO_AGAIN:
- if (skb_flow_dissect_allowed(&num_hdrs))
- goto proto_again;
- goto out_good;
- case FLOW_DISSECT_RET_CONTINUE:
- case FLOW_DISSECT_RET_IPPROTO_AGAIN:
- break;
- case FLOW_DISSECT_RET_OUT_BAD:
- default:
- goto out_bad;
- }
- ip_proto_again:
- fdret = FLOW_DISSECT_RET_CONTINUE;
- switch (ip_proto) {
- case IPPROTO_GRE:
- fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
- target_container, data,
- &proto, &nhoff, &hlen, flags);
- break;
- case NEXTHDR_HOP:
- case NEXTHDR_ROUTING:
- case NEXTHDR_DEST: {
- u8 _opthdr[2], *opthdr;
- if (proto != htons(ETH_P_IPV6))
- break;
- opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
- data, hlen, &_opthdr);
- if (!opthdr) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- ip_proto = opthdr[0];
- nhoff += (opthdr[1] + 1) << 3;
- fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
- break;
- }
- case NEXTHDR_FRAGMENT: {
- struct frag_hdr _fh, *fh;
- if (proto != htons(ETH_P_IPV6))
- break;
- fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
- data, hlen, &_fh);
- if (!fh) {
- fdret = FLOW_DISSECT_RET_OUT_BAD;
- break;
- }
- key_control->flags |= FLOW_DIS_IS_FRAGMENT;
- nhoff += sizeof(_fh);
- ip_proto = fh->nexthdr;
- if (!(fh->frag_off & htons(IP6_OFFSET))) {
- key_control->flags |= FLOW_DIS_FIRST_FRAG;
- if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
- fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
- break;
- }
- }
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- case IPPROTO_IPIP:
- proto = htons(ETH_P_IP);
- key_control->flags |= FLOW_DIS_ENCAPSULATION;
- if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- case IPPROTO_IPV6:
- proto = htons(ETH_P_IPV6);
- key_control->flags |= FLOW_DIS_ENCAPSULATION;
- if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
- fdret = FLOW_DISSECT_RET_OUT_GOOD;
- break;
- }
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- case IPPROTO_MPLS:
- proto = htons(ETH_P_MPLS_UC);
- fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
- break;
- case IPPROTO_TCP:
- __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
- data, nhoff, hlen);
- break;
- default:
- break;
- }
- if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS) &&
- !(key_control->flags & FLOW_DIS_IS_FRAGMENT)) {
- key_ports = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_PORTS,
- target_container);
- key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
- data, hlen);
- }
- if (dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ICMP)) {
- key_icmp = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_ICMP,
- target_container);
- key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
- }
- /* Process result of IP proto processing */
- switch (fdret) {
- case FLOW_DISSECT_RET_PROTO_AGAIN:
- if (skb_flow_dissect_allowed(&num_hdrs))
- goto proto_again;
- break;
- case FLOW_DISSECT_RET_IPPROTO_AGAIN:
- if (skb_flow_dissect_allowed(&num_hdrs))
- goto ip_proto_again;
- break;
- case FLOW_DISSECT_RET_OUT_GOOD:
- case FLOW_DISSECT_RET_CONTINUE:
- break;
- case FLOW_DISSECT_RET_OUT_BAD:
- default:
- goto out_bad;
- }
- out_good:
- ret = true;
- out:
- key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
- key_basic->n_proto = proto;
- key_basic->ip_proto = ip_proto;
- return ret;
- out_bad:
- ret = false;
- goto out;
- }
- EXPORT_SYMBOL(__skb_flow_dissect);
- static siphash_key_t hashrnd __read_mostly;
- static __always_inline void __flow_hash_secret_init(void)
- {
- net_get_random_once(&hashrnd, sizeof(hashrnd));
- }
- static const void *flow_keys_hash_start(const struct flow_keys *flow)
- {
- BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
- return &flow->FLOW_KEYS_HASH_START_FIELD;
- }
- static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
- {
- size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
- BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
- sizeof(*flow) - sizeof(flow->addrs));
- switch (flow->control.addr_type) {
- case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
- diff -= sizeof(flow->addrs.v4addrs);
- break;
- case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
- diff -= sizeof(flow->addrs.v6addrs);
- break;
- case FLOW_DISSECTOR_KEY_TIPC:
- diff -= sizeof(flow->addrs.tipckey);
- break;
- }
- return sizeof(*flow) - diff;
- }
- __be32 flow_get_u32_src(const struct flow_keys *flow)
- {
- switch (flow->control.addr_type) {
- case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
- return flow->addrs.v4addrs.src;
- case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
- return (__force __be32)ipv6_addr_hash(
- &flow->addrs.v6addrs.src);
- case FLOW_DISSECTOR_KEY_TIPC:
- return flow->addrs.tipckey.key;
- default:
- return 0;
- }
- }
- EXPORT_SYMBOL(flow_get_u32_src);
- __be32 flow_get_u32_dst(const struct flow_keys *flow)
- {
- switch (flow->control.addr_type) {
- case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
- return flow->addrs.v4addrs.dst;
- case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
- return (__force __be32)ipv6_addr_hash(
- &flow->addrs.v6addrs.dst);
- default:
- return 0;
- }
- }
- EXPORT_SYMBOL(flow_get_u32_dst);
- static inline void __flow_hash_consistentify(struct flow_keys *keys)
- {
- int addr_diff, i;
- switch (keys->control.addr_type) {
- case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
- addr_diff = (__force u32)keys->addrs.v4addrs.dst -
- (__force u32)keys->addrs.v4addrs.src;
- if ((addr_diff < 0) ||
- (addr_diff == 0 &&
- ((__force u16)keys->ports.dst <
- (__force u16)keys->ports.src))) {
- swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
- swap(keys->ports.src, keys->ports.dst);
- }
- break;
- case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
- addr_diff = memcmp(&keys->addrs.v6addrs.dst,
- &keys->addrs.v6addrs.src,
- sizeof(keys->addrs.v6addrs.dst));
- if ((addr_diff < 0) ||
- (addr_diff == 0 &&
- ((__force u16)keys->ports.dst <
- (__force u16)keys->ports.src))) {
- for (i = 0; i < 4; i++)
- swap(keys->addrs.v6addrs.src.s6_addr32[i],
- keys->addrs.v6addrs.dst.s6_addr32[i]);
- swap(keys->ports.src, keys->ports.dst);
- }
- break;
- }
- }
- static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
- const siphash_key_t *keyval)
- {
- u32 hash;
- __flow_hash_consistentify(keys);
- hash = siphash(flow_keys_hash_start(keys),
- flow_keys_hash_length(keys), keyval);
- if (!hash)
- hash = 1;
- return hash;
- }
- u32 flow_hash_from_keys(struct flow_keys *keys)
- {
- __flow_hash_secret_init();
- return __flow_hash_from_keys(keys, &hashrnd);
- }
- EXPORT_SYMBOL(flow_hash_from_keys);
- static inline u32 ___skb_get_hash(const struct sk_buff *skb,
- struct flow_keys *keys,
- const siphash_key_t *keyval)
- {
- skb_flow_dissect_flow_keys(skb, keys,
- FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
- return __flow_hash_from_keys(keys, keyval);
- }
- struct _flow_keys_digest_data {
- __be16 n_proto;
- u8 ip_proto;
- u8 padding;
- __be32 ports;
- __be32 src;
- __be32 dst;
- };
- void make_flow_keys_digest(struct flow_keys_digest *digest,
- const struct flow_keys *flow)
- {
- struct _flow_keys_digest_data *data =
- (struct _flow_keys_digest_data *)digest;
- BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
- memset(digest, 0, sizeof(*digest));
- data->n_proto = flow->basic.n_proto;
- data->ip_proto = flow->basic.ip_proto;
- data->ports = flow->ports.ports;
- data->src = flow->addrs.v4addrs.src;
- data->dst = flow->addrs.v4addrs.dst;
- }
- EXPORT_SYMBOL(make_flow_keys_digest);
- static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
- u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
- {
- struct flow_keys keys;
- __flow_hash_secret_init();
- memset(&keys, 0, sizeof(keys));
- __skb_flow_dissect(skb, &flow_keys_dissector_symmetric, &keys,
- NULL, 0, 0, 0,
- FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
- return __flow_hash_from_keys(&keys, &hashrnd);
- }
- EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
- /**
- * __skb_get_hash: calculate a flow hash
- * @skb: sk_buff to calculate flow hash from
- *
- * This function calculates a flow hash based on src/dst addresses
- * and src/dst port numbers. Sets hash in skb to non-zero hash value
- * on success, zero indicates no valid hash. Also, sets l4_hash in skb
- * if hash is a canonical 4-tuple hash over transport ports.
- */
- void __skb_get_hash(struct sk_buff *skb)
- {
- struct flow_keys keys;
- u32 hash;
- __flow_hash_secret_init();
- hash = ___skb_get_hash(skb, &keys, &hashrnd);
- __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
- }
- EXPORT_SYMBOL(__skb_get_hash);
- __u32 skb_get_hash_perturb(const struct sk_buff *skb,
- const siphash_key_t *perturb)
- {
- struct flow_keys keys;
- return ___skb_get_hash(skb, &keys, perturb);
- }
- EXPORT_SYMBOL(skb_get_hash_perturb);
- u32 __skb_get_poff(const struct sk_buff *skb, void *data,
- const struct flow_keys_basic *keys, int hlen)
- {
- u32 poff = keys->control.thoff;
- /* skip L4 headers for fragments after the first */
- if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
- !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
- return poff;
- switch (keys->basic.ip_proto) {
- case IPPROTO_TCP: {
- /* access doff as u8 to avoid unaligned access */
- const u8 *doff;
- u8 _doff;
- doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
- data, hlen, &_doff);
- if (!doff)
- return poff;
- poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
- break;
- }
- case IPPROTO_UDP:
- case IPPROTO_UDPLITE:
- poff += sizeof(struct udphdr);
- break;
- /* For the rest, we do not really care about header
- * extensions at this point for now.
- */
- case IPPROTO_ICMP:
- poff += sizeof(struct icmphdr);
- break;
- case IPPROTO_ICMPV6:
- poff += sizeof(struct icmp6hdr);
- break;
- case IPPROTO_IGMP:
- poff += sizeof(struct igmphdr);
- break;
- case IPPROTO_DCCP:
- poff += sizeof(struct dccp_hdr);
- break;
- case IPPROTO_SCTP:
- poff += sizeof(struct sctphdr);
- break;
- }
- return poff;
- }
- /**
- * skb_get_poff - get the offset to the payload
- * @skb: sk_buff to get the payload offset from
- *
- * The function will get the offset to the payload as far as it could
- * be dissected. The main user is currently BPF, so that we can dynamically
- * truncate packets without needing to push actual payload to the user
- * space and can analyze headers only, instead.
- */
- u32 skb_get_poff(const struct sk_buff *skb)
- {
- struct flow_keys_basic keys;
- if (!skb_flow_dissect_flow_keys_basic(skb, &keys, NULL, 0, 0, 0, 0))
- return 0;
- return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
- }
- __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
- {
- memset(keys, 0, sizeof(*keys));
- memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
- sizeof(keys->addrs.v6addrs.src));
- memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
- sizeof(keys->addrs.v6addrs.dst));
- keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
- keys->ports.src = fl6->fl6_sport;
- keys->ports.dst = fl6->fl6_dport;
- keys->keyid.keyid = fl6->fl6_gre_key;
- keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
- keys->basic.ip_proto = fl6->flowi6_proto;
- return flow_hash_from_keys(keys);
- }
- EXPORT_SYMBOL(__get_hash_from_flowi6);
- static const struct flow_dissector_key flow_keys_dissector_keys[] = {
- {
- .key_id = FLOW_DISSECTOR_KEY_CONTROL,
- .offset = offsetof(struct flow_keys, control),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_BASIC,
- .offset = offsetof(struct flow_keys, basic),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
- .offset = offsetof(struct flow_keys, addrs.v4addrs),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
- .offset = offsetof(struct flow_keys, addrs.v6addrs),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_TIPC,
- .offset = offsetof(struct flow_keys, addrs.tipckey),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_PORTS,
- .offset = offsetof(struct flow_keys, ports),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_VLAN,
- .offset = offsetof(struct flow_keys, vlan),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
- .offset = offsetof(struct flow_keys, tags),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
- .offset = offsetof(struct flow_keys, keyid),
- },
- };
- static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
- {
- .key_id = FLOW_DISSECTOR_KEY_CONTROL,
- .offset = offsetof(struct flow_keys, control),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_BASIC,
- .offset = offsetof(struct flow_keys, basic),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
- .offset = offsetof(struct flow_keys, addrs.v4addrs),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
- .offset = offsetof(struct flow_keys, addrs.v6addrs),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_PORTS,
- .offset = offsetof(struct flow_keys, ports),
- },
- };
- static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
- {
- .key_id = FLOW_DISSECTOR_KEY_CONTROL,
- .offset = offsetof(struct flow_keys, control),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_BASIC,
- .offset = offsetof(struct flow_keys, basic),
- },
- };
- struct flow_dissector flow_keys_dissector __read_mostly;
- EXPORT_SYMBOL(flow_keys_dissector);
- struct flow_dissector flow_keys_basic_dissector __read_mostly;
- EXPORT_SYMBOL(flow_keys_basic_dissector);
- static int __init init_default_flow_dissectors(void)
- {
- skb_flow_dissector_init(&flow_keys_dissector,
- flow_keys_dissector_keys,
- ARRAY_SIZE(flow_keys_dissector_keys));
- skb_flow_dissector_init(&flow_keys_dissector_symmetric,
- flow_keys_dissector_symmetric_keys,
- ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
- skb_flow_dissector_init(&flow_keys_basic_dissector,
- flow_keys_basic_dissector_keys,
- ARRAY_SIZE(flow_keys_basic_dissector_keys));
- return 0;
- }
- core_initcall(init_default_flow_dissectors);
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